Driving clutch operated by means of a roller blind tape from the lower collection casing

Abstract: It is based on a cylindrical case with cover (2) and a strip steel (4) rolled around a central socket (5) with its free end bored (12) and fixed to the socket by means of hooks (6). This socket houses, in turn, a clutch socket (1) attached to the cover and body of the case while the lower end of the strip steel is fixed by means of another bore (11) to a pin (3) protruding from the case.

Description: OBJECT OF THE INVENTION The invention refers to a clutch system for lower collection casing for roller blind tapes which consists of a case with a cover housing a mechanism encompassing two single internal components: a serrated socket and a strip steel, as well as an external clutch socket where the casing is incorporated. BACKGROUND OF THE INVENTION The rolling and fixing systems for blind rollers are well known in the art, as well as those more recent ones which incorporate these devices inside the drum on the shaft of the blind roller or on its lower tape roller. The clutch devices offer different fixing solutions depending on whether the solution chosen is incorporated into the drum of the shaft of the blind roller or inside the lower tape roller case near the lowest level of the extended blind roller. The technological solution offered by a clutch incorporated into the drum of the shaft of the blind roller (for instance, Spanish Utility Models U9102552 or U9202311) is different that the solution proposed herein and needs the installation of a larger number of components. Another possible solution, within the lower rolling case of the tape calls for the fixing of the clutch to the cover which, in turn, entails the installation of additional components in both elements. On the other hand, and for cost reasons, strip steels have become widely used and are fixed to the socket by means of rivets. This solution is not a practical one since, normally, the tension of the strip steel tends to break the rivet which adds to the problems posed by the insertion of the rivet. Document DE-B-1132690 and Document EP-A-0096137 show the use of spring inside the casing body, spring which is joined by one of its ends to a central socket and by the other end to the inner side of the cylindrical case body. The proposed invention solves the problems previously described by reducing on the one hand the number of components of the clutch system to a minimum number and, on the other hand, by conferring multiple uses to such components. Additionally, the design of one of the components solves the mechanical problem posed by the tension at the end of the strip steel since an additional intermediate operation during the assembly consisting of a 90º turn makes it impossible to detach the strip steel from its fixing point. DESCRIPTION OF THE INVENTION According to the invention there is provided a driving clutch system having the features as defined in claim 1. The clutch operated rolling device for a roller blind tape essentially comprises a metal cylindrical case body with a cover and a shaft axially extending between the body and the cover, and a steel strip attached at one end to the internal periphery of the case body and rollable around the shaft from its other inner end. The steel strip is attached to the internal periphery of the case body with the aid of a double headed pin which simultaneously supports the lower end of the roller blind tape. Previously, it is necessary to cut such roller blind tape by means of heat, since tapes are normally made of plastic. The steel strip incorporates a central slot wherein one side of the double headed pin is introduced. Taking into consideration the different characteristics of the material of the steel strip, the central slot has the shape of a keyhole so that the pins enters through its circular section and the tension of the steel strip forces the pin to be housed towards the other end of the cut. The steel strip is fixed to a first tubular socket, which surrounds concentrically the shaft that extends between the body and the cover, by means of a central oppening of said inner end fitted between two spaced hooks extending from said tubular socket with opposed angles. Both hooks are made by making a slot in two U-shaped elements with opposed openings in the socket itself. The tension of the steel strip prevents the deformation of the hooks, and the only possibility of separating the steel strip from the hooks requires the case to be opened and the steel strip to be deliberated extracted. This first tubular socket also incorporates at each of its ends a triangular-shaped tooth extending inwardly, being permanently housed inside recesses of a second tubular socket or clutch socket concentrically placed between said first socket and the shaft. When the steel strip turns along with the clutch case, the other end does not slide with respect to the main shaft due to this wedge effect of the teeth on the second tubular socket and on a keyslot of the shaft. DESCRIPTION OF THE DRAWINGS To complement this description and in an effort to better understand the main characteristics of the invention, a set of drawings is attached to this descriptive report forming an integral part of it and where, as an illustration and without limitation, the following has been represented: Figure 1 shows a general detached perspective view of the clutch casing showing the enhancements which are the object of this invention. Figure 2 shows a partial perspective view of the assembly formed by the shaft of the case, the clutch socket, the first tubular socket and the lower end of the strip steel already assembled. Figure 3 shows a cross-sectional view of figure 2. Figure 4 shows a front and side view of the tape rolling case with the clutch attached. DESCRIPTION OF THE PREFERRED EMBODIMENT It is described a preferred way to carry on the present invention relating to a driving clutch system for operating a roller blind tape from a lower collection casing, which is of the type of driving clutch systems that comprises, a cylindrical case body (2) with a cover, a shaft (9) axially extending between the body and the cover, fixed to both and provided with a common central passing bore, and a steel strip (4) attached at one end to the internal periphery of the case body and rollable around the shaft from its other inner end. Appart from this basic configuration of the driving clutch system, it can be noticed that the inner end of the steel strip (4) is fixed to a first tubular socket (5) through a central opening (12) of said inner end fitted between two axially spaced hooks (6) extending from said first socket (5) with opposed angles. Said first socket (5) additionally incorporates at each of its ends a triangular-shaped tooth (7) extending inwardly toward the axis of the socket (5) and made by cutting and bending inwardly said ends, said teeth (7) being permanently housed inside recesses of a second clutch socket (1) placed concentrically inside the first socket (5) and surrounding concentrically the shaft (9). Said second socket (1) being longer than the first socket (5) and presenting at both ends two similar diametrically opposed recesses larger that the thickness of the teeth so that once the teeth are engaged into the recesses there is room enough toward each edge of the second socket (1), to fix two keys (10) attached to a keyslot of the shaft (9). Furthermore, the outer end of the steel strip incorporates a central slot (11) where a double headed pin (3) is attached and fixes one the one hand the steel strip (4) to the inner side of the cylindrical case body (2), while on the other hand fixes the roller blind tape to the outer side of the cylindrical case body by introducing the pin head into a slot previously cut in the central part of the lower end of said roller blind tape. It is not the intention to describe further this invention since any expert on the subject will be able to understand it easily on the basis of the information provided to appreciate the scope of this invention and its advantages and to reproduce it. It is understood that, provided that the essentials of this invention are not altered, any variations in the materials or in the shape, size and layout of the elements can be introduced.

Claims: Driving clutch system for operating a roller blind tape from a lower collection casing, said system comprising a cylindrical case body (2) with a cover, a shaft (9) axially extending between the body and the cover, fixed to both and provided with a common central passing bore, and a steel strip (4) attached at one end to the internal periphery of the case body and rollable around the shaft from its other inner end, characterized in that the inner end of the steel strip (4) is fixed to a first tubular socket (5) through a central opening (12) of said inner end fitted between two axially spaced hooks (6) extending from said first socket (5) with opposed angles, said first socket (5) additionally incorporating at each of its ends a triangular-shaped tooth (7) extending inwardly toward the axis of the socket (5) and made by cutting and bending inwardly said ends, said teeth (7) being permanently housed inside recesses of a second clutch socket (1) placed concentrically inside the first socket (5) and surrounding concentrically the shaft (9), said second socket (1) being longer than the first socket (5) and presenting at both ends two similar diametrically opposed recesses larger that the thickness of the teeth so that once the teeth are engaged into the recesses there is room enough toward each edge of the second socket (1), to fix two keys (10) attached to a keyslot of the shaft (9). Driving clutch system for operating a roller blind tape from a lower collection casing according to claim 1 characterized in that the outer end of the steel strip (4) incorporates a central slot (11) where a double headed pin (3) is attached and fixes one the one hand the steel strip (4) to the inner side of the cylindrical case body (2), while on the other hand fixes the roller blind tape to the outer side of the cylindrical case body by introducing the pin head into a slot previously cut in the central part of the lower end of said roller blind tape.

Inventors: GUILLEN CHICO FRANCISCO, GUILLEN CHICO, FRANCISCO
Applicants: VINALOPO HERRAMIENTAS SL, HERRAMIENTAS DEL VINALOPO, S.L.
Application year: 1994
Main classification: E06B9
IPC codes: E06B9